This invention relates to a power generator for recovering energy in a useful form from automobiles and trucks which are leaving freeway off ramps. When automobiles and trucks approach a freeway off ramp they contain a large amount of kinetic energy. As they brake to slow down and perhaps stop at the off ramp, this energy is wasted by dissipation in the brake drums. The principal object of this invention is to provide means for converting a portion of this wasted energy into useful form.
One means for doing this which has been proposed in the past is disclosed in U.S. Pat. No. 3,885,163 which issued on May 20, 1975 to Charles E. Toberman. This patent proposes to mount a plurality of rollers in open trenches which are cut transversely across the freeway and to place the rollers so they will contact the tires of automobiles and trucks passing thereover and be rotated by frictional contact with the tires. Electrical generators are coupled to the shafts of the rollers and are rotated to change the rotational energy of the rollers into electrical energy.
This proposal has several drawbacks. In the first place, the hammering effect of repeated short periods of impact with fast moving vehicles would damage or destroy the bearings of the rollers in a short period of time. Secondly, the motorist would object to the repeated small bumps caused by the contact with the rollers. Thirdly, the open trenches would fill with water whenever it rains and thus would damage the bearings of the rollers.